package com.note.redisLock;

/**
 * @ClassName ThreadLocalTest
 * @Description TODO
 * @Author QiBin
 * @Date 2020/6/1017:03
 * @Version 1.0
 **/

import java.util.Random;

/**
 * ThreadLocal类及应用技巧
 *
 * 将线程范围内共享数据进行封装，封装到一个单独的数据类中，提供设置获取方法
 * 将该类单例化，提供获取实例对象的方法，获取到的实例对象是已经封装好的当前线程范围内的对象
 */
public class ThreadLocalTest {

    private static ThreadLocal<Integer> x = new ThreadLocal<Integer>();
    //private static ThreadLocal<MyThreadScopeData> myThreadScopeData = new ThreadLocal<MyThreadScopeData>();
    public static void main(String[] args) {
        for(int i=0;i<2;i++){
            new Thread(new Runnable(){
                @Override
                public void run() {
                    int data = new Random().nextInt();
                    System.out.println(Thread.currentThread().getName() + " has put data :" + data);
                    x.set(data);

                    /*
                    MyThreadScopeData myData = new MyThreadScopeData();
                    myData.setName("name" + data);
                    myData.setAge(data);
                    myThreadScopeData.set(myData);
                    */
                    MyThreadScopeData.getThreadInstance().setName("name" + data);
                    MyThreadScopeData.getThreadInstance().setAge(data);
                    new A().get();
                    new B().get();
                }
            }).start();
        }
    }

    //使用获取到的线程范围内的对象实例调用相应方法
    static class A{
        public void get(){
            int data = x.get();
            System.out.println("A from " + Thread.currentThread().getName() + " get data :" + data);

            /*
            MyThreadScopeData myData = myThreadScopeData.get();
            System.out.println("A from " + Thread.currentThread().getName()
                    + " getMyData: " + myData.getName() + "," + myData.getAge());
            */
            MyThreadScopeData myData = MyThreadScopeData.getThreadInstance();
            System.out.println("A from " + Thread.currentThread().getName()
                    + " getMyData: " + myData.getName() + "," + myData.getAge());
        }
    }

    //使用获取到的线程范围内的对象实例调用相应方法
    static class B{
        public void get(){
            int data = x.get();
            System.out.println("B from " + Thread.currentThread().getName() + " get data :" + data);

            MyThreadScopeData myData = MyThreadScopeData.getThreadInstance();
            System.out.println("B from " + Thread.currentThread().getName()
                    + " getMyData: " + myData.getName() + "," + myData.getAge());
        }
    }
}


class MyThreadScopeData {

    // 单例
    private MyThreadScopeData() {
    }

    // 提供获取实例方法，不加synchronized关键字表示线程各拿各自的数据，互不干扰
    public static/* synchronized */MyThreadScopeData getThreadInstance() {
        // 从当前线程范围内数据集中获取实例对象
        MyThreadScopeData instance = map.get();
        if (instance == null) {
            instance = new MyThreadScopeData();
            map.set(instance);
        }
        return instance;
    }

    // 将实例对象存入当前线程范围内数据集中
    private static ThreadLocal<MyThreadScopeData> map = new ThreadLocal<MyThreadScopeData>();

    private String name;
    private int age;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}
